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Make sure you don't have gout. It tends to manifest itself in situations like yours.
sciatica
You didn't mention what sort of footwear you use.
My 2012 V7R (old 5 speed) caused me the same problems. I bought some Sidi Doha boots and solved the problem. Transmission eventually got easier to shift as well.
BTW, rearsets move the whole footpeg/shifter assembly aft. They do not provide a heal shift point.
You can find standard heel-toe shifters, but, I found most are made for floorboards and interfere with the foot on the peg.